Write down steps to measure the thickness of a cylinder with the help of:?

Question

1) vernier calliper

2) s***w gauge

Answer 1

Let's assume that you already know what these instruments are but you want to know how to use them.  

If not, the vernier caliper and the s***w gauge both have jaws that contact the object to be measured on either side of the thickness.  The difference is that the vernier slides the jaws together and the s***w uses a s***w motion to move the jaws.  

As with all measurements there is some uncertainty in the reading taken.  This uncertainty can be reduced by proper orientation of the jaws to assure contact in the normal, meaning perpendicular to the surface.  

Unfortunately, a cylinder has some curvature, which makes the thickness of the jaws important, too..You can imagine that the jaw might be so wide that a gap under it against the curve of the cylinder will make the cylinder seem thicker than it truly is.  Small, narrow jaws will help minimize this effect.  

The measurement error itself, even though minimized by proper tool usage, will still exist.  

The reference article is quite good at explaining the procedure.  

The vernier scale is designed to expand the small differences onto a much larger length.  The length is carefully marked with divisions that are spaced apart about 99 times the spacing of the main scale and line up exactly with the numbers in the decimal part of the measurement.  The "0" on the vernier marks the integer part of the measurement, while the next mark location that lines up exactly with the main scale is the fractional part of the measurment.  

The s***w gauge is similar in function but the scale is wrapped around the tool.  The integer part is exposed and the fractional part appears on the rotating dial.  The exposed integer can be a fraction, too, such as integer plus a half -- so the dial reading has to be added to the exposed main reading.  

The steps then would be:

1.  Zero your vernier by closing the instrument and adjusting the reading to be exactly 0.00

2.  Open the tool and gently clamp the tool around the object to be measured, gently sidling it into proper position so that it is as perpendicular to the surface as possible, and closing it down to make full contact

3.  Take the main (most significant) reading off the main scale

4.  Read off the least significant digits from the vernier

5.  Combine the most and least significant readings to find an answer

6.  Estimate the error range for the reading